MGD LECTURE 2.1 ENZYME ACTIVITY: KINETICS AND INHIBITION Flashcards
Whats is an enzyme?
Biological catalyst which increases rate of reaction by lowering activation energy
What do enzymes facilitate the formation of?
The transition state, also known as a high energy intermediate
What are active sites?
Usually clefts or crevices which exclude water. Complementary shape to that of substrate.
What is induced fit model?
Binding of substrate induces changes in conformation of enzyme
How big is an enzymes active site?
> 100 amino acids
How are substrates bound to enzymes?
By all types of non-covalent bonds
What is Vo?
initial rate of reaction
how does an increase of temperature affect enzyme function?
increases number of molecules with activation energy
How does an increase in concentration of substrate affect enzyme function?
increases chance of molecular collisions
What is KM?
substrate conc which gives half maximal velocity
What is Vmax?
Maximal rate when all enzyme active sites are saturated with substrate
What does the michaelis menten equation predict?
A plot of Vo versus S will be a rectangular hyperbole
What does it mean if an enzyme has a low km?
high affinity for its substrate
What does the lineweaver burk plot allow for?
Easy estimation of km (gradient = km/vmax) and vmax (y intercept is 1/vmax)
What is an enzyme inhibitor?
A molecule that slows down or prevents an enzyme reaction.
